Dehydrator



June 16, 1925. 1,542,616

i c. A. GREEN nmDRA'r'on Filed Aug. 26, 1922 2 Shun-She a 2 I I W l Patented June 16.1925

UNITED STATES QHA L A. GREEN; WH US R DA ass sNba BY were ASSIGNMENTS.

A GQRPORATION OF FLORIDA.

.TO FLORID DEHYDRATING AND 'rREs n-arneco, or i oKsgmrrLnn, roning,

DEHYDBATQB! 'Application filed August 26,;1922. Seriallto. 584,456.- a

To all whom it may concern:

Be "it known that 1, CHARLES A. GREEN, a citizen of the'United- States, residing; at -Whitchouse, inthe county of Duval and 5 State of Floridafhave inventedcertain new and useful Improvements inDehydrators, of which the following is aspe'cification. I

My inventionrelates to an apparatus for dehydrating food-stuffs and other commodities by means ofheated air.

The main and particular objects and ad vantages of invention are, to provide a dehydrator consisting of interchangeable units, which may be assembled in any number; so astoincrease or decrease its capacity, and to so construct theseunits that thedehydator may be usedeither as a portable or stationary apparatus.

These and other objects and advantages will be clearly understood from the following specification and from the accompanying drawing of a preferredembodiment of my invention, but it willbe understood that Various modificationsmightbe made without departing from the scope of the invention. 49 Fig. 1 is front elevation, showing two nnits of the dehydrator connected together. One unit is shown with the door closeda-nd theother unit with the door open, so as to expose the dehydrating chamber.

'Figz2 is a plan viewof Fig. 1.

Fig. Sis a sectionalside'elevation of one unit as indicated byline 3+3 on'Fig. 1. A part of the side bafileplate broken away show the trays and tray bafile plates; v F 4 is a sectional plan View of two units ,asindicated by linei t i on Fig. 1, and shows the arrangement tofthe fs'team further object is to provide a dehydrator which willbe economic 1n operat1on,

coils which heat the air before it enters the dehydrating chamber.

l -ig. 5 is i a perspective View' of a tray "and a tray, bafile plate on theirrespective supports and also shows the air .Ventin th back plate. The door has been omitted.

Fig. dis a modification of the tray and tray baille plate show-nin Fig. -5'. i

Fig. 7 I is a side elevation of-a sidebafile hlit shutter; v

Fig-Sis adetail View of the damper. In a general'waythe dehydrator may be said to consist ofan outermetal cabinet having a door in front and air passages on its outer sides extending nearly to the top. Near the bottom of thecab-inet a steam heating coil is placed which causes the air entering through the side air passages to become heated.

pieced vertically on the door and back plate,

respectively, and these flues are, by means of 9;

suitable pipes and pipe fittings connected with an air exhaust fan, which keeps the air circulation constant. "Any number of units may be connectedtogether using steam from the same boiler and having their air circulation'supplied by one fan.

The apparatus will now beexplained in detail; similar parts of the two units-are indicated by similar numerals. g

Referring first to Figs. 1 and 2, the dehydrator consists of a base plate 1, which in this case rests on two iron beams 2; these beams extend the full length of all the units to the inn'erside plates 5 at the points 6 and extend, slightlyfcurx ed, toward the points 8 where they terminate, thus forming an This heated air is then passed up through inner air passages and by means of baflle plates distributed through the trays,' placed in an inner or dehydrating chamber. After the air has passed through the trays it is drawn out through openings. formedin the doorand back plate of the apparatus. These openings communicate with due pipes elongated opening 9. It is through this opening that the air enters the heating chamber.

The outer side plates 3, the inner side plates 5, as well as the inner bottom plates 7 extend the whole depth of the apparatus. Where the outer side plates 3 terminate at the top openings 10 are formed, these openings also extend the whole depth of the apparatus. Between the outer side plates 3 and the inner side plates 5 air passages 11 are formed. In like manner air passages 12 are formedbetweenthe base plate 1 and the inner bottom plates 7. Thusthe outside air is free to pass through openings 10, air

passages 11 and 12, and opening 9 into the air heating chamber 13 in which steam heating coils are placed.

By referring to Figs. 3 and at, the steam coils and their construction will be readily understood. A steam supply pipe 14: connects with a boiler, not shown on the drawing; at regularly spaced distances this pipe is provided with pipe fittings 15 and 16 which supply steam to each separate unit.

The coils, as shown, consist of pipes 17 connected at their ends with return elbows 18. The center pipe being of larger dimension than the rest on account of having to feed to the coils on either side.

- The extreme outer pipes in the coils are connected by means of pipe fittings 19 to the return pipe 20; this plpe carries the condensing water and return steam back to the boiler; Each coil feed pipe is connected to the steam supply pipe by a steam valve 21. For the sake of ease in assembling, the steam pipe 1 1 as well as the return pipe 20 are supplied with union couplings 22 and 23. Right back of the valve 21, in the center coil pipe 17, a hole is drilled and tapped, and into this hole a short pipe 2 1 is screwed; the other end of pipe 24 is connected with a steam cock 25 into which is screwed a perforated pipe 26. The purpose of this cock and perforated pipe will be explained later.

Referring again to Fig. 1, the roof or top plate 27, of the air heating chamber 13, also forms the bottom plate of the inner or dehydrating compartment This inner compartment is formed, in addition to the plate 27, by side baffle plates 28 and the top plate 1 and extends the whole depth of the apparatus. It will be seen that air passages 29 are formed between the side baffle plates 28 and the inner side plates 5, thus the air, after being heated in the air chamber 13, passes through openings at both sides of this chamber into air passages 29. These openings, which lead into the passages 29 and which extend the whole depth of the apparatus, are provided with dampers 30 for controlling the flow of air; Handles 31 for operating these dampers extend through the front of the dehydrator. One of the dampers is plainly shown in Fig. 8.

Referring now to Fig. 3, the side bafile plates and their construction will be explained. The baffle plates 28 extend clear to the top plate 4. A plurality of horizon tal rows of rectangular slots or openings 32 are cut in the baffle plates, in front of these rows of slots shutters 33 are slidably mounted. These shutters are also provided with rows of slots 3 1, corresponding in size and location to the slots 32. By means of the shutters 33 the size of the openings 32 may be diminished or entirely closed. The shutters are also provided with guide rods 35 and 36, sliding in holes in the front and rear walls, and with knobs or handles 37.

The slots 32, as well as the construction and operation of the shutters 33, are plainly shown in the two lower rows on Fig. 3. The shutter is removed from the lower row to show the slots 32 and the shutter in the row immediately above is partly drawn forward, thus partly closing the slots All the other shutters are shown open. The location of the horizontal rows of slots is such that they will be directly below the trays placed in the inner compartment. It will be noted that the air passages 29 are tapered so that they narrow down at the top. This is done to distribute the heated air evenly through the horizontal rows of slots.

Referring again to Fig. 1, in the inner compartn'ient the removable trays 38 are placed and on these trays the material to be dehydrated is spread. The trays 38 consist of a rectangular metal or wood frame and are provided with wire mesh bottoms. The trays are supported on angle iron supports 39, riveted to the inner sides of the baflle plates 28, and are free to slide on these supports. Between each shelf and over and under the upper and lower trays, removable tray baffle plates 10 are placed. These tray bafile plates are slightly curved so as to distribute the air which flows over them evenly through the wire mesh bottoms of the trays above. These bafiie plates are, likethe trays, supported on angle iron supports 41 riveted to the side baffle plates and are free to move on these supports.

As the heated air passes up through the air passage 29 it flows through the slots 34 in shutters 33 and through the slots 32 in side baffle plate 28 and enters the space between the tray baffle plate 10 and the tray 38, whereupon it rises through the wire mesh in the bottoms of the trays. This flow of the heated air willbe readily understood by referring to Fig. 5 in which, for convenience of explanation, the shutters 33 have been removed and only part of the wire mesh shown. 2

After the heated air has passed through the trays 38 it is drawn toward the front openings 48, placed directly above each of the trays, and these openings communicate with a semicircular flue 44 which extends vertically from below the lowest openings?) to some distance above the apparatus. This fine is "rigidly attached to the back plate. The door 4.5 is similarly provided with openings46 and flue 47. The fiue et? termihates a short'distance above the door so that when the door is closed this flue willmake anrair tight joint with a continuation 48 of the flue attached on the top plate 4.

As the flue 44 and flue continuation 458 rise above the top plate,'their semicircular cross: section 1s gradually changed to circulay and these circular parts are connected by pipes 4.9'and 50 to a'main suction pipe 51; At the end of this pipe a suction fan, not shown on the drawing, operates.

Dampers 552, connected by levers 53 toan operating handle bar 54, are placed in the pipes 49 and 50. The door :4t5 is provided with hinges 5'5 and latches 56, these latches are connected with a bar 57 to facilitate their operationw A door jamb 58 covers such parts of the front 01" the apparatus as is not covered by the door. 7 In*Fig.'6 a modification of thetrays an tray baflie plates is shown. In this modification the baffle plate..59 has upturned side walls 60 by means'of'which the baffle plate is attached to the frame 61' of the tray. The bottom-oi theftrafy is covered with wire mesh 62 and openings63, similar in size and corresponding to theloca'tion of the openings 82 in the side bafile plates "28, are cut in the side walls 60. When these trays are used the angle iron supports T3f9are omitted and the trays slide on the angle iron sup ports 41.

The operation of the dehydrator is as follows:

The material to be dehydrated having been spread on the trays 38, these trays are inserted in their places and the door 45 is closed. The steam from the boiler enters the steam coil located in the chamber 13 through the pipe 14. lVhen the fan, connected to the pipe 51, is started a current of air is drawn through the apparatus. Air

from the outside is drawn through the openings 10 into the heating chamber, as previously explained. In the heating chamber 13 the air is heated to the required temperature; this heated air is now drawn up through the inner air. passages 29 and dis tributed through the openings 32 between thetrays38 and their respective bafile plates 40. It will be noted that any heat which may be radiated through the side plates 5 will not be lost, but will'tend to preheat the "air passing downthrough theouter air pasrial will absorb the moisture contained This moisture laden air is drawn out through the openings 43 and 46 and therein.

into the fines 4-4 and 47 andisfinallyexpelled from'the apparatus by the .fan.

The reason for having the tray baflie' plates removableis to facilitate the cleaningof these as wellas of the whole-apparatus. The modified trays 61, with bafile plates 59 attached, are used'for such materialsas when dehydrating haveatendency. to fallthrough thewire-mesh 62, such particles as fall through will be emptied out together with the materials on the trays, when these are raised on end.

'As it is sometimes advisable to partly blanch the material, just before starting the a process of dehydration, the perforated pipe 26 iszprovided. After the door 45 has been closed the steam cook '25 is opened and steam enters the apparatus through the perforated pipe, after a certain interval, varying with the materials treated, the fan is started and the steam drawn off together with the moisture laden air. The steam cock 25 isthen closedand the process carried on as before described. r

It will beunderstood that this apparatus may be provided- .with thermostatic heat controls and moisture regulating devices and that any other-suitableconstruction of Iclaim: y 1. In a'dehydrating apparatus; an :air

'a heating coil,.than the one described,-might e be employed.

heating chamber, having meansfor heating f the air passing through it; means for dividing the heated air into two currents; tapered hot air passages for evenly distributing these currents; the inner walls of said tapered hot air passages provided with horizontal rows of passages communicating with the dehydrating compartment; and said rows of passages so situated as to direct the currents directly under each tray in the dehydrating compartment. r

2. In a dehydrating apparatus; an air heating chamber; means for dividing the alr heated 111 said chamber into two currents; f

tapered hot air passages for evenly. distributing these currents; the inner walls of said tapered hot air passages provided with horizontal rows of passages communicating with i the dehydrating compartment; said rows of passages so. situated as to direct the currents directly under each tray in the dehydrating compartment; and shutters for regulating the size of said passages.

3.v In a dehydrating apparatus; an air heating chamber; means for dividing the air heated in said chamber into two currents; tapered hot air passages for evenly distributing these currents; the inner walls of said tapered hot air passages provided with horizontal rows of shutter controlled passages communicating with the dehydrating compartment; and removable trays and tray bafile plates alternately placed in said dehydrating compartment and so located that the heated air will enter between the tray and the tray baflle plates.

4.1n a dehydrating apparatus; an air heating chamber; tapered hot air passages on opposite sides of the apparatus; the inner walls of said tapered hot air passages provided with horizontal rows of shutter controlled passages for directing the heated air into the dehydrating compartment directly under each tray; and tray baffle plates placed between each tray directing the air towards passages placed above the trays in the door and rear wall of the dehydrating compartment.

5. In a dehydrating apparatus; an air heating chamber; tapered hot air passages on opposite sides of the apparatus; the inner walls of said tapered hot air passages pro vided with horizontal rows of passages communicating with the dehydrating compartment and directing the flow of air between the trays and tray baffle plates; passages formed in the front and rear of the dehydrating compartment above each tray; and verticalflues into which said air currents are discharged.

I 6. In a dehydrating apparatus; an air heating chamber; tapered hot air passages on opposite sides of the apparatus; the inner walls of said tapered hot air passages provided with horizontal rows of passages communicating with the dehydrating compartment and directing the flow of air between the trays and tray bailie plates; passages formed in the front and rear of the dehydrating compartment above each tray; and vertical flues connected by damper controlled pipes to an air exhaust pipe.

7.. In a dehydrating apparatus,. of the class described; an air heating chamber;

tapered hot air passages on opposite sides of the apparatus; horizontal rows oi passages formed in the inner walls of said tapered hot air passages for directing the heated air into tray battle plates attached rigidly ,to trays; and said trays arranged one above another in the dehydrating compartment; the tray batlie plate above each tray directing the air towards passages in the front and rear of the said dehydrating compartment.

8. In a dehydrating apparatus; an air heating chamber; tapered hot air passages on opposite sides of the apparatus; the inner walls of said tapered hot air passages pro added with horizontal rows of passages communicating with the dehydrating compartment and directing the flow of air between the trays and tray bafl'le plates; passages formed in the front and rear of the dehydrating compartment above each tray; vertical fiues connected by damper controlled pipes to an air exhaust pipe; and one or more perforated pipes extending. into the air heating chamber for moistening the heated air.

In testimony whereof, I .CHARLns A. GREEN have signed my name to this specification in the presence of two subscribing witnesses, this 28th day of July 1922.

CHARLES A. GREEN.

Witnesses AUG. J. HOEKSTRA, JOHN EATON. 

